41 research outputs found

    A Modified Spectral Methods for Large-Scale UnconStrained

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    A modified spectral methods for solving unconstrained optimization problems based on the formulae are derived which are given in [4, 5]. The proposed methods satisfied the descent condition. Moreover, we prove that the new spectral methods are globally convergent. The Numerical results show that the proposed methods effective by comparing with the FR-method

    Two Versions of the Spectral Nonlinear Conjugate Gradient Method

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    The nonlinear conjugate gradient method is widely used to solve unconstrained optimization problems. In this paper the development of different versions of nonlinear conjugate gradient methods with global convergence properties proved. Numerical results indicated that the proposed method is very efficient

    An enhanced fletcher-reeves-like conjugate gradient methods for image restoration

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    Noise is an unavoidable aspect of modern camera technology, causing a decline in the overall visual quality of the images. Efforts are underway to diminish noise without compromising essential image features like edges, corners, and other intricate structures. Numerous techniques have already been suggested by many researchers for noise reduction, each with its unique set of benefits and drawbacks. Denoising images is a basic challenge in image processing. We describe a two-phase approach for removing impulse noise in this study. The adaptive median filter (AMF) for salt-and-pepper noise identifies noise candidates in the first phase. The second step minimizes an edge-preserving regularization function using a novel hybrid conjugate gradient approach. To generate the new improved search direction, the new algorithm takes advantage of two well-known successful conjugate gradient techniques. The descent property and global convergence are proven for the new methods. The obtained numerical results reveal that, when applied to image restoration, the new algorithms are superior to the classical fletcher reeves (FR) method in the same domain in terms of maintaining image quality and efficiency

    Assessment of Cox2 and CMV in patients with chronic HCV infection

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    Objective This study was established to determine the expression of COX-2 and CMV in patients with chronic C infection. Methods A total of 30 formalin-fixed of paraffin-embedded liver samples obtained from patients with chronic hepatitis C infection. In addition, 30 apparently normal liver autopsies were used as control group used for immunohistochemistry technique (IHC) to study the expression of cyclooxygenase (COX-2) and cytomegalovirus (CMV) in these samples. Results In current study, the results of expression of COX-2 were found in 25 cases (83.3%) of chronic HCV were strongly positive with a significant increase at P < 0.001, while the result of CMV expression was detected as brown cytoplasmic membranous staining of cells with positive CMV expression demonstrated in 21 (70.0%) out of 30 cases of chronic HCV infection cases. All control groups were negative for the expression of COX-2 and CMV. Conclusion This study concludes that COX-2 and CMV participates in the pathogenesis of chronic HCV infection. Keywords chronic HCV infection, cyclooxygenase (COX-2), cytomegalovirus (CMV

    A novel four-wing chaotic system with multiple equilibriums: Dynamical analysis, multistability, circuit simulation and pseudo random number generator (PRNG) based on the voice encryption

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    Recently, there has been tremendous interest worldwide in the possibility of using chaos in communication systems. Many different chaos-based secure communication schemes have been proposed up until now. However, systems with strong chaoticity are more suitable for chaos-based secure communication. From the viewpoint of Lyapunov exponents, a chaotic system with a larger positive Lyapunov exponent is said to be more complex. This paper constructing a multistable chaotic system that can produce coexisting attractors is an attractive field of research due to its theoretical and practical usefulness. An innovative 3D dynamical system is presented in this research. It can display various coexisting attractors for the same values of parameters. The new system is more suitable for chaos-based applications than recently reported systems since it exhibits strong multistable chaotic behavior, as proved by its large positive Lyapunov exponent. Furthermore, the accuracy of the numerical calculation and the system's physical implementations are confirmed by analog circuit simulation. Finally, implementing the proposed voice encryption is done using a four-wing chaotic system based on the PRNG

    PREVALENCE AND POTENTIAL RISK FACTORS OF HEPATITIS B VIRUS IN A SAMPLE OF CHILDREN IN TWO SELECTED AREAS IN YEMEN

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    Objective: The global epidemic of hepatitis B is a significant public health problem. The endemicity of HBV infection used to be believed high in Yemen. Data for the prevalence of HBsAg among children in rural and urban areas in Yemen is scarce and incompetent. The study was made to determine prevalence of HB surface antigen among children in 2 selected areas in Yemen. Methods: Eight hundred forty and 212 children were randomly chosen from Sana'a city and Shabowah governorate, respectively. Sera were tested for HBs antigen by ELISA technique, and HB genome was tested for positive HB surface antigen specimens to confirm positivity using polymerase chain reaction (PCR)-based test. Each data collected in a pre-designed questionnaire including sex, age, and risk factors of HBV and prior vaccine of HBV. Results: The prevalence of HB surface antigen among children in Sana'a city was only 1.8%, and in Shabowah governorate was 3.8%. There was a significant association of non-vaccinated children, birth by cesarean, and with a history of parental exposure with contracting HBV infection.Conclusion: Evidence from these studies in Yemen suggests that there is a steady increase in exposure to HBV over a lifetime. Hospital-acquired HBV infection is common in Yemen, and high vaccination coverage rate should be achieved, particularly in rural areas, in parallel with health education. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Peer Review History: Received 21 June 2019; &nbsp;&nbsp;Revised 6 July; Accepted 10 July, Available online 15 July 2019 Academic Editor: Dr. Amany Mohamed Alboghdadly, Princess Nourah bint abdulrahman university, Riyadh, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Reviewer's Comments: Average Peer review marks at initial stage: 6.5/10 Average Peer review marks at publication stage: 8.5/10 Reviewer(s) detail: Aya Mohammed Mohammed Essawy, MTI University- Mokattam, Egypt, [email protected] Dr. Dalia Kamal Zaffar Ali,&nbsp;Modern University for technology and information, Egypt,&nbsp;[email protected] Similar Articles: SERO-EPIDEMIOLOGICAL STUDY OF HEPATITIS B, C, HIV AND TREPONEMA PALLIDUM AMONG BLOOD DONORS IN HODEIDA CITY- YEMEN EXPLOSION OF HEPATITIS B AND C VIRUSES AMONG HEMODIALYSIS PATIENTS AS A RESULT OF HEMODIALYSIS CRISIS IN YEME

    Abstracts from the 3rd International Genomic Medicine Conference (3rd IGMC 2015)

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    A New Hybrid Conjugate Gradient Method with Guaranteed Descent for Unconstraint Optimization

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    The conjugate gradient method an efficient technique for solving the unconstrained optimization problem. In this paper, we propose a new hybrid nonlinear conjugate gradient methods, which have the descent at every iteration and globally convergence properties under certain conditions. The numerical results show that new hybrid method are efficient for the given test problems

    A New Nonlinear Conjugate Gradient Method Based on the Scaled Matrix

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    In this paper, a new type nonlinear conjugate gradient method based on the Scale Matrix is derived. The new method has the decent and globally convergent properties under some assumptions. Numerical results indicate the efficiency of this method to solve the given test problems
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